Is there any way to control this forsythia?

I have a lovely but enormous forsythia growing by the corner of my garage. It’s in the narrow strip of yard (maybe 14 ft wide) between the garage wall and the neighbor’s fence. Earlier this year, I had the Man “trim” it–one person’s trimming is another person’s cutting-off-at-knee-height–and thought it was a goner for sure, but no! It’s now completely filling the yard again and is as tall as the rain gutters.
I don’t mind a forsythia there–it’s beautiful in the spring and it creates a little “Secret Garden” area behind it. But unless I can control it, the Secret Garden is also known as the Completely Inaccessible Garden.
Do I just keep trimming it? Around here most people just plant them on the property line and let them go, but I can’t do that or it’ll take over my garage and eventually my neighbor’s as well.

In the house where I grew up we had a privacy hedge of forsythia. Every year after it bloomed, we’d trim it back so it wouldn’t overpower the adjacent sidewalk. It just kept getting thicker and taller. I think once forsythia finds a place it likes, you have to try hard to kill it. So prune it back as much as you need to, and enjoy it!

Nuke it from space, it is the only way.

We have been combatting a forsythia for 10 years … we think it is winning. Sometime this winter it is meeting mr Chainsaw and mr Toxic Plant Poison. We are planting something less allergy inducing for me like lilac.

I wouldn’t mind keeping it if I could reduce it’s circumference…it’s just so damn big around that if I want to be able to get into the Secret Garden, I’ll have to trim it twice a year. At least. Man, it grows fast.